Blast or exhaust apparatus



(NoModeL) 3 Sheets-Sheet 1.

J. Y. SMITH.

BLAST 0R EXHAUST APPARATUS.

No. 386,502. Patented July 24, 1888.

7 125 neyo",

3 Sheet-Sheet 2.

(No Model.)

J. Y. SMITH.

BLAST OR EXHAUST APPARATUS.

No. 386,502. PatentedJuly 24, 1888.

minesaes I 7417/6 71:6 or

N. PETERS. Plwmum m hnr. Wmhmmm n c.

(No Model.) 3 Sheets-Sheet 3;

J. Y. SMITH.

BLAST 0R EXHAUST APPARATUS.

,502. Patented July 24, 1888.

mine-336,8. Inventor.

' 7L '5 Jiiorne ys,

N PETERS Mala-Lithographer. Washington, D. C.

Uniin STATES ATENT @FFICEQ JOHN Y. SMITH, OF DOYLESTO\VN, PENNSYLVANIA.

BLAST OR EXHAUST APPARATUS.

SPECIFICATION forming part of Letters Patent No. 386,502, dated July24,1888.

Application filed January 11, 1888. Serial No. -3130, 104.

(N0 model.)

Patented in Eng and November 14, 13b7, No. 15,573.

To aZZ whom it may concern:

Be it known that I, JOHN Y. SMITH, of Doylestown, in the county of Bucksand State of Pennsylvania, have invented certain new and usefulImprovements in Blast or Exhaust Apparatus, (for a portion of which Ihave obtained a patent in Great Britain.No. 15,573, bearing dateNovember 14, 1887;) and I do hereby declare the following to be a full,clear, and exact description of the same, reference being had to theaccompanying drawings, forming a part of this specification, and to thefigures and letters of reference marked thereon.

This in vention relates to a new and improved blast or exhaust apparatusdesigned more especially for use in connection withlocomotive and otherboilers or furnaces for inducing, maintaining, and regulating the draft;and my said invention embraces certain modifications in, improvementsupon, and additions to the apparatus disclosed in my application, No.250,929, filed September 28, 1887, Patent No. 378,340.

The principal and distinguishing elements of my present invention may bebriefly stated as follows: First, the employment ofindependentconliuing-chambers for theinner and outer ejectors; second, the additionof a third confining line or chamber into which the inner and outer ejectors dischargaeither directly or through an intervening minglingchamber or passage, with inlet-openings so arranged and disposed as toform a third ejector; third, a movable section or damper interposedbetween the ejector and the escape-orifice leading to the smoke-stack orchimney, said damper or movable section forming part of or made separatefrom the ejector and operating to control the escape of the products ofcombustion from the srnoke=box or uptake into the chimney orsmoke-stack, whereby said products may be admitted directly into thechimney or compelled to pass in whole orin part through the ejector;and, fifth, the employment of a compression-chamber communicating withthe steam-passage below the jet opening or nozzle for preventingback-pressure in the exhaustchamber and for prolonging or supplementingthe direct action of the blast.

'Iheinvention also includes certain other and minor improvementsrelating to the construction, arrangement, and combination of parts,

as hereinafter more fully deseribcd,and pointed out in the claims.

In the accompanying drawings, wherein my said inventions areillustrated, Figures 1 and 2 are end and side views, respectively,partly in section, showing the location and arrangcment of the ejectingapparatus within the smokebox or uptake of a locomotive-boiler. Fig. 3is a longitudinal vertical section through an ejector illustrating theapplication ofa portion of my present improvements. Pig. 4 isa similarview illustrating slight modifications in the construction andarrangement of the parts. Fig. 5 is a longitudinal vertical sectionthrough an ejector embodying features common to the ejectors, Figs. 3and 4, and in addition thereto illustrating the application and use ofthe compression-chamber. Figs. 6 and 7 are transverse horizontalsections on lines was and y y, Fig. 5. Fig. 8 is a longitudinal verticalsection through an ejector, illustrating a modification of my inventionto adapt it for use in connection with a solid as distinguished from anannular central steamjet. Fig. 9 is a section on lineazr, Fig. 8.

Similar letters of reference in the several figures indicate the sameparts.

Referring more particularly to Figs. 1 and 2, A represents thesmokechamber; B, the fines; O, the smoke-stack or chimney; D D, thechambers or passages into which exhauststeamis delivered from thecylinders; E the bridge-wall or partition between said exhaustchambers;and F, the ejector or exhaust appa ratus opening into the base of thesmoke-stack.

Between the upper or eduction end of the blast apparatus and the openinginto the smoke-stack an adjustable hood or confiningflue, l, isinterposed, so arranged that it can be moved to cover or uncover theopening into the Smokestack. In the present instance the fine 1 is shownsupported by eyes 2 upon vertical rods 3, a bell-crank or other lever,4, engaging the flue and attached to a connectingrod, 5, extending backto the cab in position to be manipulated by the engineer, serving as aready and convenient means for effecting the vertical adjustment.

The upper end of the flue 1 is adapted to [it against or within theopening in the base of the smokestack, and its lower end,preferablyprovided with a flaring month or deflecting 2 ssto plate, is formed withan opening somewhat larger than the external diameter of the ejector orblast apparatus F, a space or passage being formed between the flneandejector communieating with the smoke-box. As thus arranged, and bymaking the flue l vertically adjustable, it is made to perform twodistinct functions, inasmuch as it serves both as a damper and as a partof the supplemental ejector; hence it may properly be regarded as anembodiment of or illustration of two different features, the one amovable damperinterposcd between the mouth of the ejector or blastapparatus for controlling the passage between the smoke-box and chimney,and the other as a portion of asupplemental blast apparatus or ejector,the gases and steam under pressure as delivered from the ejector Fwithin'said flue serving to draw the gases or air through the passagebetween the flueand exterior of the ejector and force it into theSmokestack.

It will be observed that the flue 1, acting in its capacity as a damper,is supported in a manner to permit of a vertical movement, so that whenlowered it will uncover the entrance to the smoke-stack and permit theheated products of combustion to passfrom thesrnoke-box directly intothe chimney where it is impelled either by natural or forced draft orboth combined; but when said flue is elevated, as shown in the drawings,it will cut off or close the direct-draft opening and compel the gasesand products of combustion to pass through and be acted upon by theblast apparatus or some portion thereof before entering the smokestack.

As before stated, an annular or other shaped opening or passage isformed between the exterior of the blast apparatus and the line 1,through which the gases are drawn by the ac tion of theblast within saidflue, the latter constitutinga confining-chamber for receiving the gasor air and steam as delivered from the blast apparatus F. While thissupplemental air-passage is desirable, as enlarging the ca pacity of thedraftinducing device, it is not essential to the complete operation ofthe invention in other respects, as will presently appear.

The special application or use of the movable flue l, regarded as adamper or valve for directing the products of combustion, or a portionthereof,into the chimney or smoke-stack, either wholly or partiallythrough the blast or exhaust apparatus, is to secure a more regular andeven draft and prevent backpressure in the smoke-stack or uptake.

As iswell known, the blast or exhaust apparatus heretofore employed onlocomotiveboilers is usually located within the smokebox and with itsjet-orifice in line with the opening in the Smokestack, but removed atsome distance from the walls of the latter, and the supply of steam istaken from the exhaustports ofthe cylinders. Consequently the blast isdelivered in the form of successive jets or blasts of steam under greatpressure.

The steam issuing from the jet-orifice is driven or propelled into andagainstthe column of rarefied gaseous matter within the smock-stack,and, moving at a high rate of speed, drives a certain portion of thegaseous matter before it into and through the smoke stack.

Each blast of steam may be regarded as a separate piston traversing thesmoke-stack at a high rate of speed, while at the same time it expandslaterally, thereby increasingin area,

its maximum speed and minimum area coinciding at the point of entranceinto the smokestack and its maximum area and minimum speed at point ofexit therefrom.

The area of the blast of steam as compared with the opening in thesmoke-stack and the high velocity at which the steam is driven are suchthat not only is a very large portion of the available power of theexhaust-steam wasted, but the fluctuations in pressure due to theintermitting action of the blast are reproduced with increasedviolencein the fines and furnace. This defective action is due, in ameasure, to the manner of applying the blast as well as tothe characterof the blast or exhaust apparatus employed.

The relatively small jet or blast of steam when projected into the muchlarger column of highly -heated gaseous matter operates mainly bydisplacement, and forces the gaseous matter to one side, thereby formingeddies and interfering currents within the smokebox; and as the jet orblast of steam in its passage through the smoke stack acts largely byfriction against the gases contained therein, while its speed diminishesin proportion as it nears the exit end of the smoke-stack, its effectiveaction upon the body of gas in the smoke-box is not only diminished, butit sometimes happens that between successive blasts a partial return ordownward movement takes place in the smoke-stack, the influence ofwhichis felt in the smoke box, tlues, and furnace. It is for the purposeof in a measure overcoming or diminishing these defects that the flue 1is interposed between the blast or exhaust apparatus and the opening inthe smoke-stack, whereby all the products of combustion may be divertedinto and brought under the direct influence of the blast apparatus,thereby increasing the effective action of the steam and at the sametime preventing the formation of eddies and counter-currents in thesmoke-box andsmoke-stack, such as are produced by lateral displacementwhen a blast of steam is discharged into the column of heated gases andbeneath the open end of the smoke-stack. Moreover, by making the flue 1movable vertically, instead of laterally, it can be employed as a damperto more or less completely close the passage between the smoke-stack andsmoke-box without materially interfering with its action as part of thesupplemental ejector, whereby the force of the draft may be regulatedwhile the steam is freely escaping through the ejector and withico outproducing back-pressure; and by dropping the tlue 1 so as to entirelyuncover the opening into the smokestack the furnace can be run bynatural draft, as when starting up the fire or when the engine isstanding.

Blast or exhaust apparatus of various forms and constructions may beemployed for ind ucing a draft up and through the smoke-stack, but Iprefer to use an exhaust apparatus of the character shown in thedrawings and belonging to the particular type described in mybefore-mentioned prior applicationthat is to say, an apparatus providedwith two separate ejector-s so combined and united as to form a singleexhaust or blast apparatus, and with induction-ports located atdifferent levels within the smoke-box or relatively to the fine. Such anapparatus is illustrated in Figs. 3, 4, and 5, wherein A designates thecentral airtube or inletpassage communicating through ind action-passage10 with the space surrounding thcapparatus; B, the annular steam spaceor nozzle communicating through passage or chamber 11 with thesteanrchest; O, the confining flue or passage into which the blast ofsteam from nozzle 13 is delivered, and acting upon and against thecolumn of air draws the latter through opening A and forces it into andthrough said flue C. The parts A B together constitute what is hereintermed the inner ejectoflor exhaustapparatus. Sun

rounding the inner ejector and extending to or beyond the mouth ofitsconfining-flue G- is a wall or casing, F between which latter and saidflue C is formed a second confining flue or passage, F, into which opensan air passage or inlet, D, and an annular steam passage or nozzle, E.The parts F D E constitute the outer ejector.

It will be observed that in each case the blast devices of the inner andouter ejectors are provided with and deliver into independent confiningchambers or passages, and that both of said passages C and F open ordeliver into the interior of line 1, either directly, as in Fig. 5, orthrough an intermediate mingling chamber or passage, F, formed by aprolonga tion of the outer wall, F", beyond the mouth of fine 0.

The air-passage Dof the outer ejector communicates through inletpassages or ports 13 with the exterior of the apparatus at a point orpoints abovctheinletlt) of theinnerejector, whereby the air and gaseswill be drawn from different levels and the draft distributed throughthe fines.

From an inspection of the drawings and a consideration of the mutual andcooperative relation of the several parts thus far mentioned, it will beobvious to one skilled in the art that when steam under pressure isadmitted and caused to flow through the nozzles B and E the jets issuingtherefrom will operate to d raw the air and gases through passages A andl), and that the air drawn through passage A, as it is carried into flueC, will be surrounded by and intimately mingled with the steam issuingfrom nozzle B, while the air drawn through passage D will in like mannerbe intimately associated with the steam from nozzle E, and that thematerials,whether solid, liquid, or gaseous, issuing from the twoejectors will be associated together while retained under pressure andin motion, first in the mingling-chamber, when the latter is employed,and afterward in the confining-flue 1, into which an additional chargeof air or gaseous matter is drawn through the passage between tlue 1 andexterior of the ejector proper.

It is to be understood that the area of the two nozzles B E is the sameor may exceed that of the single nozzle heretofore commonly employed, sothat a free escape for exhauststeam is permitted. At the same time theeffective action of the steam is increased by distributing it over alarger surface and cansing it to operate upon the air and gases issuingfrom relative long and narrow openings, whereby a thin body of steam isbrought in contact with a thin enveloping column of air or gas, so thata more intimate admixture takes place within the confining -chamber.This feature is of considerable importance as contributing to theextinguishment of sparks.

As it is sometimes desirable to modify the action of the blast, a valve,15, is arranged to co-operate with the steanrports leading to nozzle E.Said valve may be annular in form and connected to pivoted links 16 byball-andsocket or other flexible connections-such as will permitthevalve to rotate, and in so doing will cause it to be rcciprocated towardand from its seat by the toggle action of the links. In devices of thiskind great difficulty is experienced in keeping valves clean andpreventing stieking, and especially is this the case where, as in thepresent instance, the valves are subjected to the action of steamcharged with oil or othcrlubricating material. Under the action of heatand pressure the oil supplied to the cylinders is partially decomposedby the steam, and the product being carried over by the exhaust depositsupon the valve and its seat, forming a thick obstructing coating, whichnot only interferes with the proper working of the valve by its merepresence, but forms an active corroding agent which attacks the metaland destroys the valve-surfaces, besides adding to the material of theinterfering coating the products of the corrosive action on the metal.This has heretofore been regarded as such aserious defect as to causeengineers to discard and object to the employment of blast or exhaustapparatus wherein valves alone were employed or depended upon toregulate or adjust the draft. By the use of the compound orspirally-movablc valve, sliding into contact with its seat, but entirelyremoved therefrom when the stcamports are opened, some of theseobjections are overcome, but not such as are due alone to the corrosiveaction ofthe decomposed lubricants. To obviate this defect and increasethe durability or life of the valve, I construct the wearing or contactsurfaces of glass, asbestus, or other silieious ma terial, which may beaccomplished by the insertion of said materials within a groove orrecess, as shown in Figs. 3 and 4.

The ejectors, Figs. 3 and 4, are included herein merely as illustratingcertain modifications in form and improvements in the structure andoperation of the ejector claimed in my prior application and for thepurpose of showing the application thereto of the valve and theconfining chamber of the outer ejector, and with the exceptions named noclaim is made herein to the improvements in the construction andarrangement of parts, said subjectmatter being reserved for anotherapplication, Serial No. 273,355.

The preferredbecause the most complete and satisfactory-form or type ofejector is illustrated in Fig. 5.

The relative position and arrangement of the component parts of theinner and outer ejectors are su bst-antially the same as thatsh own inthe apparatus, Fig. 4, the principal changes made being the Shorteningof flue O and the lengthening of line or air-pipe A to bring the steamand air nozzles nearer the center.

As is usual, the passages leading to, and in fact constituting, thenozzles B and E, through which steam is injected, are preferably soformed that the contiguous walls or surfaces shall be caused to approachor be brought nearest together at a point somewhat below the ends of thepsssages and diverge slightly, but uniformly, toward the mouth, in orderthat the steam may be slightly retarded and compressed at the contractedpart of the passage, and emerging ther from shall be conducted betweenthe diverging surfaces to the month, where, by expansion and pressure,it acts most powerfully upon the inelosed column of air or gases tocarry and force the latter into and through the confining-flue anddeliver it into the smoke stack, either directly, or preferably througha supplemental flue, 1.

The two cylinders of a locomotive discharge their exhaust-steamalternately on opposite sides of the blast or exhaust apparatus, andwhere, as in the present case, the latter is designed and arranged toreceive the exhaust from both cylinders it is essential, first, that aclear passage and free outlet for the steam should be provided, in orderthat the escape of the exhaust should meet with but slight resistance;and, second, that the exhaust from one cylinder should be prevented asmuch as possible from entering the exhaust-passage of the oppositecylinder, as in either case objectionable back-pressure will beproduced.

With a view to overcoming, or at the least greatly reducing, excessiveback-pressure on the cylinders and their exhaust, the crosspiece 26,through which air is conducted to the inner ejector, is extendeddownward, so as to rest upon or cooperate with the bridge-wall orpartition E in forming a division between the two exhaust-passages. (SeeFigs. 5 and 1.) The sides of the lower section or steam-chamber arecurved or extended laterally, and the top edge of the cross'piece 26 isnarrowed or beveled, so as to form two separate converging passages, 17,each communicating at one end with the exhaust passage or chamberleading to one of the cylinders, and both of said passages 17 convergingtoward and opening into the steam-space below the nozzle of the innerejector, whereby a large open passage is provided for each exhaust, andthe steam admitted through one of said passages is directed upward andaway from the opposite passage and delivered directly into the nozzle.In this way the exhaust-steam from both cylinders is conveyed directlyto and distributed throughout the whole area of the blast orifice ornozzle, whereit is somewhat retarded in its escape by the contractedform of the opening. The blast otsteam,moving at a high speed and underpressure, being thus suddenly checked or retarded in its movement towardthe escape-orifice, will, unless pre vented from so doing, react and byexpansion be forced downward. or toward the exhaustpassage leading tothe opposite cylinder, and meeting the steam therein will producebackpressure on the exhaust. To prevent this very defective andobjectionable action, common to most blast devices where two or morecylinders are caused to exhaust into a common ejector, and to increasethe effective work of the ejector, I provide a compressionchamber toreceive and hold the steam as it rebounds or is forced back by the wallsof the contracted nozzle, said compression-chamber being maintained inopen communication with the nozzle or blast-orifice, and serving both asa receptacle to receive and sustain, in partat least, the

back-pressure, and as areservoir for the storage of power which isexpelled, as the pressure of the inducingblast ceases or diminishes tosustain orsupplement said blast,and thereby prolong or increase thepower of the ejector.

The apparatus shown in Fig. 5 illustrates one embodiment of this featureof my invention. admitted to the outer ejector, are formed near butbelow the nozzle of the innerejector, so as to communicate both with theouter nozzle, E, or the steanrpassage leading thereto, and thecompressionchamber 19. In the present instance this compression-chamberis located at the base of the outer ejector and below the ports 18, thelatter controlled by a valve, 20, arranged to be actuated from theexterior by a rackand -pinion connection, 21, or other equivalentdevices. As thus arranged, when a blast of steam is delivered to theejector through one of the exhaust-passages,and is directed toward thenozzle of the inner ejector, it flows through the ports 18, and as it ischecked or retarded at the contracted mouths of the two ejectors areaction at once takes place, and as there must be a preponderance ofpressure in the central passage, due to the inertia of the larger bodyof steam, as well as the pressure of the lower end of the column,

The ports 18, through which steam is.

the steam enters and is compressed within the chamber 19 until thepressure in the nozzles is diminished, as by the escape of steamtherethrough, when it is permitted to escape into the nozzles, thussupplementing and prolonging the primary impulse.

The use of the compressionchamber is not restricted to the particulartype of ejector illustrated in Fig. 5, but may be used in connectionwith a single steam-nozzle or a double ejector provided with a centralsolid as distinguished from an annular nozzle, as shown in Fig. 8. Herethe outer ejector, in all respects substantially the same as that in Fi5, is constructed separately from and adapted to be detachably securedto a steam pipe or nozzle, N, steam being conducted to the outer ejectorthrough passages 30, and a space or passage, 31, formed between saidpipe N and the outer ejector, through which the gaseous matter is drawnby the central jet or column of steam. In order, however, to carry theexhaust-passages up nearer the nozzle, as well as to increase thecapacity of the ejector, I prefer to add to or supplement the ordinaryblast-pipe by the insertion of a hollow bridge-wall, 32, in the lowerend of said pipe and above the bridge-wall of the exhaust-chamber, withinletopenings 38 at the sides and an opening, 34, at the top and withinpipe N. Extending across the mouth of opening 34, and paralleltherewith, isa division-plate, 35, whose opposite edges are beveled orinclined toward the center to form an expanding passage on each side,while below said opening 34 the walls of the passages are slightlyconverged, as at 36. As thus arranged, the blast of steam from eitherside is caused to draw a portion of air or gases through the opening atthe top of the bridge 32 and discharge into pipe N between thebridge-wall nozzle and passages 30.

The detachable outer ejector, with its compression-chamber, and thebridge-wall 32, with its divison-plate 35, can either or both be appliedto the blastpipes in common use, the only adaption necessary being theformation of suitable openings for the insertion of the bridgewall andto communicate with pas sages 30.

Should it for any reason he desired to employ but a single ejector, thevalve governing the ports leading to the outer ejector may be closed andthe outer ejector removed by withdrawing the fastenings at the base,(see Fig. 5,) or the outer ejector, Fig. 8, can be lifted ofi and theopenings closed by a ring or other suitable means.

Having thus described my invention, what I claim as new is 1. In anexhaust apparatus of the character described, the combination, with theinner ejector, of a second or outer ejector arranged with itssteam-nozzle in advance of the steamnozzle of the inner ejector, saidejectors receiving steam from a chamber or passage common to both anddelivering into a common passage or fine through independentconfining-flucs, substantially as described.

2. In combination with the smoke-box and the chimney or smoke-stack, anexhaust apparatus, and an adjustable flue interposed between thedelivery end of the exhaust apparatus and the passage or opening intothe smoke-stack, and cooperating with the latter to close or open directcommunication between the smoke-box and smoke-stack, substantially asdescribed.

3. In combination with the smoke-stack and blast or exhaust apparatus, amovable flue interposed between the delivery end of the exhaustapparatus and the opening in the smoke-stack, said flue co-operatingwith the blast apparatus to form a supplementalejector, and with thesmoke-stack to act as a damper, substantially as described.

4. In combination with the smoke'box or uptake and the smoke-stack of alocomotiveboiler, a blast apparatus receiving steam from the cylindersand containing an inner and an outer ejector, and a vertically movableflue surrounding the delivery-end of the two ejectors and interposedbetween the latter and the opening into the smoke stack, substantiallyas described.

5. In a locomotive-boiler, and in combination with the exhaust apparatuslocated within the smoke-box, a movable flue interposed be tween thedelivery end of the exhaust apparatus and the opening into thesmoke-stack, and co operating with the latter to control the directdraft or passage from smoke-box into the smoke-stack, and adjustingdevices convenient to the engineer for actuating said movable flue,substantially as described.

6. In an exhaust apparatus for locomotive and other similar boilers,located within the smoke-box and delivering into the smokestack, saidexhaust apparatus comprising an inner injector with an inlet oppositethe lower series of dues, an outer ejector having its airinlet above theinlet of the inner ejector, a supplemental confining-chamber into whichboth ejectors deliver, and an airinlet to said chamber opening into theupper portion of the smoke-box, substantially as described.

7. In an apparatus such as described, the combination of an inner and anouter ejector, each provided with a separate confining-flue, saidconfiningflues opening into a line or passage common to both ejectors,substantially as described.

8. In an apparatus such as described, the combination of an innerejector provided with air and steam nozzles and a confining-fiue, asecond ejectorsurrounding the firstmentioned ejector and provided withan independent airsupply, steam-nozzle, and confining tube or passage,and a confining tube or line common to both of said ejectors,substantially as described.

9. In an exhaust apparatus such as described, the eombination,with aninner ejector CODI- IIO municating directly with the steam'supplypassages, of a second or outer ejector detachably secured to said innerejector and receiving steam therefrom, substantially as described.

10. In an ejector or blast apparatus, and in combination with thesteam-nozzle thereof, a

compression-chamber communicating with the steam-passage below or inrear of the nozzle, substantially as described.

11. In an ejector or blast apparatus wherein exhaust steam from acylinder or steam in suc' cessive blasts is projected into a passageleading to a nozzle or escapeorifice, and in combination with thelatter, a closed compressionchambcr communicatingwith thesteam-supplypassage, substantially as and for the purpose set forth.

12. In an exhaust apparatus such as described, and in combination withthe inner and outer ejectors, their steam passages and nozzles, thecompression-chamber communicating with both of said nozzles,substantially as described.

13. In an exhaust apparatus such as described, the combination,with aninner ejector communicating with the exhaust-steam passages, of an outerejector receiving steam through ports in said inner ejector, avalvecontrolling said ports, and a compressionchamber'conncc'ted to saidouter ejector below or in rear of said steam'ports, substantially asdescribed.

1 4. In combination with the cylinders of an engine, and theexhaust-steam passages leading therefrom, an exhaust or blast apparatussuch as described, provided with two or more separate ejector's, asteam-passage common to all the ejectors, a hollow bridgeor wallintermediate said steam-passage, and the exhauststeam passages leadingto the cylinders, substantially as described.

15. In combination with the two passages or chambers into which theexhauststeam from the cylinders is delivered, an ejector whose lower orreceiving end is divided by a hollow wall into two sections, eachcommuni' cating with one of the steam-passages leading to the cylinders,and both opening into a common passage leading to the steam-nozzle,substantially as described.

16. In an exhaust apparatus such as de scribed, the combination, withthe annular steam-nozzle and central air-tube, of the crosspicce orbridge containing an air-passage communicating with the centralair-tube, said cross-piece being provided with inclined upper edges andcooperating with the partition between the exhaustchambers of thecylinders to convey the exhaust-steam from each cylinder directly to thenozzle, substantially as described.

17. In an exhaust apparatus such as described, and in combination withtheinnerand outer ejectors and a compression-chamber, separate passagesfor receiving the exhauststeam and delivering it directly to the nozzle,substantially as described.

JOHN Y. SMITH.

Witn esses J. B. GHURoH, MELVILLE CHURCH.

